等腰梯形,角B=60° ∴角C=90°
AC平分角BAD ∴∠CAD=∠ACD=30°,∠BCA=90°
BC=AD=CO=2
则在Rt△ABC中:AB=4,AB上的h=2根号3
∴S=1/2(CD+AB)h
=1/2(2*4)*2根号3
=6根号3
等腰梯形,角B=60° ∴角C=90°
AC平分角BAD ∴∠CAD=∠ACD=30°,∠BCA=90°
BC=AD=CO=2
则在Rt△ABC中:AB=4,AB上的h=2根号3
∴S=1/2(CD+AB)h
=1/2(2*4)*2根号3
=6根号3